NVMe: Only release requested regions
[linux-2.6-block.git] / include / linux / workqueue.h
CommitLineData
1da177e4
LT
1/*
2 * workqueue.h --- work queue handling for Linux.
3 */
4
5#ifndef _LINUX_WORKQUEUE_H
6#define _LINUX_WORKQUEUE_H
7
8#include <linux/timer.h>
9#include <linux/linkage.h>
10#include <linux/bitops.h>
4e6045f1 11#include <linux/lockdep.h>
7a22ad75 12#include <linux/threads.h>
60063497 13#include <linux/atomic.h>
7a4e344c 14#include <linux/cpumask.h>
1da177e4
LT
15
16struct workqueue_struct;
17
65f27f38
DH
18struct work_struct;
19typedef void (*work_func_t)(struct work_struct *work);
d8e794df 20void delayed_work_timer_fn(unsigned long __data);
6bb49e59 21
a08727ba
LT
22/*
23 * The first word is the work queue pointer and the flags rolled into
24 * one
25 */
26#define work_data_bits(work) ((unsigned long *)(&(work)->data))
27
22df02bb
TH
28enum {
29 WORK_STRUCT_PENDING_BIT = 0, /* work item is pending execution */
8a2e8e5d 30 WORK_STRUCT_DELAYED_BIT = 1, /* work item is delayed */
112202d9 31 WORK_STRUCT_PWQ_BIT = 2, /* data points to pwq */
8a2e8e5d 32 WORK_STRUCT_LINKED_BIT = 3, /* next work is linked to this one */
22df02bb 33#ifdef CONFIG_DEBUG_OBJECTS_WORK
8a2e8e5d
TH
34 WORK_STRUCT_STATIC_BIT = 4, /* static initializer (debugobjects) */
35 WORK_STRUCT_COLOR_SHIFT = 5, /* color for workqueue flushing */
0f900049 36#else
8a2e8e5d 37 WORK_STRUCT_COLOR_SHIFT = 4, /* color for workqueue flushing */
22df02bb
TH
38#endif
39
73f53c4a
TH
40 WORK_STRUCT_COLOR_BITS = 4,
41
22df02bb 42 WORK_STRUCT_PENDING = 1 << WORK_STRUCT_PENDING_BIT,
8a2e8e5d 43 WORK_STRUCT_DELAYED = 1 << WORK_STRUCT_DELAYED_BIT,
112202d9 44 WORK_STRUCT_PWQ = 1 << WORK_STRUCT_PWQ_BIT,
affee4b2 45 WORK_STRUCT_LINKED = 1 << WORK_STRUCT_LINKED_BIT,
22df02bb
TH
46#ifdef CONFIG_DEBUG_OBJECTS_WORK
47 WORK_STRUCT_STATIC = 1 << WORK_STRUCT_STATIC_BIT,
48#else
49 WORK_STRUCT_STATIC = 0,
50#endif
51
73f53c4a
TH
52 /*
53 * The last color is no color used for works which don't
54 * participate in workqueue flushing.
55 */
56 WORK_NR_COLORS = (1 << WORK_STRUCT_COLOR_BITS) - 1,
57 WORK_NO_COLOR = WORK_NR_COLORS,
58
79bc251f 59 /* not bound to any CPU, prefer the local CPU */
f3421797 60 WORK_CPU_UNBOUND = NR_CPUS,
bdbc5dd7 61
73f53c4a 62 /*
112202d9
TH
63 * Reserve 7 bits off of pwq pointer w/ debugobjects turned off.
64 * This makes pwqs aligned to 256 bytes and allows 15 workqueue
65 * flush colors.
73f53c4a
TH
66 */
67 WORK_STRUCT_FLAG_BITS = WORK_STRUCT_COLOR_SHIFT +
68 WORK_STRUCT_COLOR_BITS,
69
112202d9 70 /* data contains off-queue information when !WORK_STRUCT_PWQ */
45d9550a 71 WORK_OFFQ_FLAG_BASE = WORK_STRUCT_COLOR_SHIFT,
bbb68dfa 72
8603e1b3
TH
73 __WORK_OFFQ_CANCELING = WORK_OFFQ_FLAG_BASE,
74 WORK_OFFQ_CANCELING = (1 << __WORK_OFFQ_CANCELING),
bbb68dfa 75
715b06b8
TH
76 /*
77 * When a work item is off queue, its high bits point to the last
7c3eed5c
TH
78 * pool it was on. Cap at 31 bits and use the highest number to
79 * indicate that no pool is associated.
715b06b8 80 */
bbb68dfa 81 WORK_OFFQ_FLAG_BITS = 1,
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TH
82 WORK_OFFQ_POOL_SHIFT = WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS,
83 WORK_OFFQ_LEFT = BITS_PER_LONG - WORK_OFFQ_POOL_SHIFT,
84 WORK_OFFQ_POOL_BITS = WORK_OFFQ_LEFT <= 31 ? WORK_OFFQ_LEFT : 31,
85 WORK_OFFQ_POOL_NONE = (1LU << WORK_OFFQ_POOL_BITS) - 1,
b5490077
TH
86
87 /* convenience constants */
0f900049 88 WORK_STRUCT_FLAG_MASK = (1UL << WORK_STRUCT_FLAG_BITS) - 1,
22df02bb 89 WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
7c3eed5c 90 WORK_STRUCT_NO_POOL = (unsigned long)WORK_OFFQ_POOL_NONE << WORK_OFFQ_POOL_SHIFT,
dcd989cb
TH
91
92 /* bit mask for work_busy() return values */
93 WORK_BUSY_PENDING = 1 << 0,
94 WORK_BUSY_RUNNING = 1 << 1,
3d1cb205
TH
95
96 /* maximum string length for set_worker_desc() */
97 WORKER_DESC_LEN = 24,
22df02bb
TH
98};
99
1da177e4 100struct work_struct {
a08727ba 101 atomic_long_t data;
1da177e4 102 struct list_head entry;
6bb49e59 103 work_func_t func;
4e6045f1
JB
104#ifdef CONFIG_LOCKDEP
105 struct lockdep_map lockdep_map;
106#endif
52bad64d
DH
107};
108
7c3eed5c 109#define WORK_DATA_INIT() ATOMIC_LONG_INIT(WORK_STRUCT_NO_POOL)
7a22ad75 110#define WORK_DATA_STATIC_INIT() \
7c3eed5c 111 ATOMIC_LONG_INIT(WORK_STRUCT_NO_POOL | WORK_STRUCT_STATIC)
a08727ba 112
52bad64d
DH
113struct delayed_work {
114 struct work_struct work;
1da177e4 115 struct timer_list timer;
60c057bc
LJ
116
117 /* target workqueue and CPU ->timer uses to queue ->work */
118 struct workqueue_struct *wq;
1265057f 119 int cpu;
1da177e4
LT
120};
121
7a4e344c
TH
122/*
123 * A struct for workqueue attributes. This can be used to change
124 * attributes of an unbound workqueue.
d55262c4
TH
125 *
126 * Unlike other fields, ->no_numa isn't a property of a worker_pool. It
127 * only modifies how apply_workqueue_attrs() select pools and thus doesn't
128 * participate in pool hash calculations or equality comparisons.
7a4e344c
TH
129 */
130struct workqueue_attrs {
131 int nice; /* nice level */
132 cpumask_var_t cpumask; /* allowed CPUs */
d55262c4 133 bool no_numa; /* disable NUMA affinity */
7a4e344c
TH
134};
135
bf6aede7
JD
136static inline struct delayed_work *to_delayed_work(struct work_struct *work)
137{
138 return container_of(work, struct delayed_work, work);
139}
140
1fa44eca
JB
141struct execute_work {
142 struct work_struct work;
143};
144
4e6045f1
JB
145#ifdef CONFIG_LOCKDEP
146/*
147 * NB: because we have to copy the lockdep_map, setting _key
148 * here is required, otherwise it could get initialised to the
149 * copy of the lockdep_map!
150 */
151#define __WORK_INIT_LOCKDEP_MAP(n, k) \
152 .lockdep_map = STATIC_LOCKDEP_MAP_INIT(n, k),
153#else
154#define __WORK_INIT_LOCKDEP_MAP(n, k)
155#endif
156
ee64e7f6
TH
157#define __WORK_INITIALIZER(n, f) { \
158 .data = WORK_DATA_STATIC_INIT(), \
159 .entry = { &(n).entry, &(n).entry }, \
160 .func = (f), \
161 __WORK_INIT_LOCKDEP_MAP(#n, &(n)) \
65f27f38
DH
162 }
163
f991b318 164#define __DELAYED_WORK_INITIALIZER(n, f, tflags) { \
ee64e7f6 165 .work = __WORK_INITIALIZER((n).work, (f)), \
f991b318 166 .timer = __TIMER_INITIALIZER(delayed_work_timer_fn, \
e0aecdd8
TH
167 0, (unsigned long)&(n), \
168 (tflags) | TIMER_IRQSAFE), \
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169 }
170
ee64e7f6 171#define DECLARE_WORK(n, f) \
65f27f38
DH
172 struct work_struct n = __WORK_INITIALIZER(n, f)
173
ee64e7f6 174#define DECLARE_DELAYED_WORK(n, f) \
f991b318 175 struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, 0)
65f27f38 176
203b42f7 177#define DECLARE_DEFERRABLE_WORK(n, f) \
f991b318 178 struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, TIMER_DEFERRABLE)
dd6414b5 179
dc186ad7
TG
180#ifdef CONFIG_DEBUG_OBJECTS_WORK
181extern void __init_work(struct work_struct *work, int onstack);
182extern void destroy_work_on_stack(struct work_struct *work);
ea2e64f2 183extern void destroy_delayed_work_on_stack(struct delayed_work *work);
4690c4ab
TH
184static inline unsigned int work_static(struct work_struct *work)
185{
22df02bb 186 return *work_data_bits(work) & WORK_STRUCT_STATIC;
4690c4ab 187}
dc186ad7
TG
188#else
189static inline void __init_work(struct work_struct *work, int onstack) { }
190static inline void destroy_work_on_stack(struct work_struct *work) { }
ea2e64f2 191static inline void destroy_delayed_work_on_stack(struct delayed_work *work) { }
4690c4ab 192static inline unsigned int work_static(struct work_struct *work) { return 0; }
dc186ad7
TG
193#endif
194
1da177e4 195/*
52bad64d 196 * initialize all of a work item in one go
a08727ba 197 *
b9049df5 198 * NOTE! No point in using "atomic_long_set()": using a direct
a08727ba
LT
199 * assignment of the work data initializer allows the compiler
200 * to generate better code.
1da177e4 201 */
4e6045f1 202#ifdef CONFIG_LOCKDEP
dc186ad7 203#define __INIT_WORK(_work, _func, _onstack) \
65f27f38 204 do { \
4e6045f1
JB
205 static struct lock_class_key __key; \
206 \
dc186ad7 207 __init_work((_work), _onstack); \
23b2e599 208 (_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
ee64e7f6 209 lockdep_init_map(&(_work)->lockdep_map, #_work, &__key, 0); \
65f27f38 210 INIT_LIST_HEAD(&(_work)->entry); \
f073f922 211 (_work)->func = (_func); \
65f27f38 212 } while (0)
4e6045f1 213#else
dc186ad7 214#define __INIT_WORK(_work, _func, _onstack) \
4e6045f1 215 do { \
dc186ad7 216 __init_work((_work), _onstack); \
4e6045f1
JB
217 (_work)->data = (atomic_long_t) WORK_DATA_INIT(); \
218 INIT_LIST_HEAD(&(_work)->entry); \
f073f922 219 (_work)->func = (_func); \
4e6045f1
JB
220 } while (0)
221#endif
65f27f38 222
ee64e7f6 223#define INIT_WORK(_work, _func) \
9da7dae9 224 __INIT_WORK((_work), (_func), 0)
dc186ad7 225
ee64e7f6 226#define INIT_WORK_ONSTACK(_work, _func) \
9da7dae9 227 __INIT_WORK((_work), (_func), 1)
dc186ad7 228
f991b318 229#define __INIT_DELAYED_WORK(_work, _func, _tflags) \
ee64e7f6
TH
230 do { \
231 INIT_WORK(&(_work)->work, (_func)); \
f991b318 232 __setup_timer(&(_work)->timer, delayed_work_timer_fn, \
e0aecdd8
TH
233 (unsigned long)(_work), \
234 (_tflags) | TIMER_IRQSAFE); \
52bad64d
DH
235 } while (0)
236
f991b318 237#define __INIT_DELAYED_WORK_ONSTACK(_work, _func, _tflags) \
ee64e7f6
TH
238 do { \
239 INIT_WORK_ONSTACK(&(_work)->work, (_func)); \
f991b318
TH
240 __setup_timer_on_stack(&(_work)->timer, \
241 delayed_work_timer_fn, \
242 (unsigned long)(_work), \
e0aecdd8 243 (_tflags) | TIMER_IRQSAFE); \
6d612b0f
PZ
244 } while (0)
245
f991b318
TH
246#define INIT_DELAYED_WORK(_work, _func) \
247 __INIT_DELAYED_WORK(_work, _func, 0)
248
249#define INIT_DELAYED_WORK_ONSTACK(_work, _func) \
250 __INIT_DELAYED_WORK_ONSTACK(_work, _func, 0)
251
203b42f7 252#define INIT_DEFERRABLE_WORK(_work, _func) \
f991b318
TH
253 __INIT_DELAYED_WORK(_work, _func, TIMER_DEFERRABLE)
254
255#define INIT_DEFERRABLE_WORK_ONSTACK(_work, _func) \
256 __INIT_DELAYED_WORK_ONSTACK(_work, _func, TIMER_DEFERRABLE)
28287033 257
365970a1
DH
258/**
259 * work_pending - Find out whether a work item is currently pending
260 * @work: The work item in question
261 */
262#define work_pending(work) \
22df02bb 263 test_bit(WORK_STRUCT_PENDING_BIT, work_data_bits(work))
365970a1
DH
264
265/**
266 * delayed_work_pending - Find out whether a delayable work item is currently
267 * pending
355c0663 268 * @w: The work item in question
365970a1 269 */
0221872a
LT
270#define delayed_work_pending(w) \
271 work_pending(&(w)->work)
365970a1 272
c54fce6e
TH
273/*
274 * Workqueue flags and constants. For details, please refer to
275 * Documentation/workqueue.txt.
276 */
97e37d7b 277enum {
c7fc77f7 278 WQ_UNBOUND = 1 << 1, /* not bound to any cpu */
58a69cb4 279 WQ_FREEZABLE = 1 << 2, /* freeze during suspend */
6370a6ad 280 WQ_MEM_RECLAIM = 1 << 3, /* may be used for memory reclaim */
649027d7 281 WQ_HIGHPRI = 1 << 4, /* high priority */
41f50094 282 WQ_CPU_INTENSIVE = 1 << 5, /* cpu intensive workqueue */
226223ab 283 WQ_SYSFS = 1 << 6, /* visible in sysfs, see wq_sysfs_register() */
b71ab8c2 284
cee22a15
VK
285 /*
286 * Per-cpu workqueues are generally preferred because they tend to
287 * show better performance thanks to cache locality. Per-cpu
288 * workqueues exclude the scheduler from choosing the CPU to
289 * execute the worker threads, which has an unfortunate side effect
290 * of increasing power consumption.
291 *
292 * The scheduler considers a CPU idle if it doesn't have any task
293 * to execute and tries to keep idle cores idle to conserve power;
294 * however, for example, a per-cpu work item scheduled from an
295 * interrupt handler on an idle CPU will force the scheduler to
296 * excute the work item on that CPU breaking the idleness, which in
297 * turn may lead to more scheduling choices which are sub-optimal
298 * in terms of power consumption.
299 *
300 * Workqueues marked with WQ_POWER_EFFICIENT are per-cpu by default
301 * but become unbound if workqueue.power_efficient kernel param is
302 * specified. Per-cpu workqueues which are identified to
303 * contribute significantly to power-consumption are identified and
304 * marked with this flag and enabling the power_efficient mode
305 * leads to noticeable power saving at the cost of small
306 * performance disadvantage.
307 *
308 * http://thread.gmane.org/gmane.linux.kernel/1480396
309 */
310 WQ_POWER_EFFICIENT = 1 << 7,
311
618b01eb 312 __WQ_DRAINING = 1 << 16, /* internal: workqueue is draining */
8719dcea 313 __WQ_ORDERED = 1 << 17, /* internal: workqueue is ordered */
23d11a58 314 __WQ_LEGACY = 1 << 18, /* internal: create*_workqueue() */
e41e704b 315
b71ab8c2 316 WQ_MAX_ACTIVE = 512, /* I like 512, better ideas? */
f3421797 317 WQ_MAX_UNBOUND_PER_CPU = 4, /* 4 * #cpus for unbound wq */
b71ab8c2 318 WQ_DFL_ACTIVE = WQ_MAX_ACTIVE / 2,
97e37d7b 319};
52bad64d 320
f3421797
TH
321/* unbound wq's aren't per-cpu, scale max_active according to #cpus */
322#define WQ_UNBOUND_MAX_ACTIVE \
323 max_t(int, WQ_MAX_ACTIVE, num_possible_cpus() * WQ_MAX_UNBOUND_PER_CPU)
65f27f38 324
d320c038
TH
325/*
326 * System-wide workqueues which are always present.
327 *
328 * system_wq is the one used by schedule[_delayed]_work[_on]().
329 * Multi-CPU multi-threaded. There are users which expect relatively
330 * short queue flush time. Don't queue works which can run for too
331 * long.
332 *
73e43544
LJ
333 * system_highpri_wq is similar to system_wq but for work items which
334 * require WQ_HIGHPRI.
335 *
d320c038
TH
336 * system_long_wq is similar to system_wq but may host long running
337 * works. Queue flushing might take relatively long.
338 *
f3421797
TH
339 * system_unbound_wq is unbound workqueue. Workers are not bound to
340 * any specific CPU, not concurrency managed, and all queued works are
341 * executed immediately as long as max_active limit is not reached and
342 * resources are available.
4149efb2 343 *
24d51add
TH
344 * system_freezable_wq is equivalent to system_wq except that it's
345 * freezable.
0668106c
VK
346 *
347 * *_power_efficient_wq are inclined towards saving power and converted
348 * into WQ_UNBOUND variants if 'wq_power_efficient' is enabled; otherwise,
349 * they are same as their non-power-efficient counterparts - e.g.
350 * system_power_efficient_wq is identical to system_wq if
351 * 'wq_power_efficient' is disabled. See WQ_POWER_EFFICIENT for more info.
d320c038
TH
352 */
353extern struct workqueue_struct *system_wq;
73e43544 354extern struct workqueue_struct *system_highpri_wq;
d320c038 355extern struct workqueue_struct *system_long_wq;
f3421797 356extern struct workqueue_struct *system_unbound_wq;
24d51add 357extern struct workqueue_struct *system_freezable_wq;
0668106c
VK
358extern struct workqueue_struct *system_power_efficient_wq;
359extern struct workqueue_struct *system_freezable_power_efficient_wq;
ae930e0f 360
4e6045f1 361extern struct workqueue_struct *
b196be89
TH
362__alloc_workqueue_key(const char *fmt, unsigned int flags, int max_active,
363 struct lock_class_key *key, const char *lock_name, ...) __printf(1, 6);
4e6045f1 364
b196be89
TH
365/**
366 * alloc_workqueue - allocate a workqueue
367 * @fmt: printf format for the name of the workqueue
368 * @flags: WQ_* flags
369 * @max_active: max in-flight work items, 0 for default
355c0663 370 * @args...: args for @fmt
b196be89
TH
371 *
372 * Allocate a workqueue with the specified parameters. For detailed
373 * information on WQ_* flags, please refer to Documentation/workqueue.txt.
374 *
375 * The __lock_name macro dance is to guarantee that single lock_class_key
376 * doesn't end up with different namesm, which isn't allowed by lockdep.
377 *
378 * RETURNS:
379 * Pointer to the allocated workqueue on success, %NULL on failure.
380 */
4e6045f1 381#ifdef CONFIG_LOCKDEP
ee64e7f6
TH
382#define alloc_workqueue(fmt, flags, max_active, args...) \
383({ \
384 static struct lock_class_key __key; \
385 const char *__lock_name; \
386 \
fada94ee 387 __lock_name = #fmt#args; \
ee64e7f6
TH
388 \
389 __alloc_workqueue_key((fmt), (flags), (max_active), \
390 &__key, __lock_name, ##args); \
4e6045f1
JB
391})
392#else
ee64e7f6
TH
393#define alloc_workqueue(fmt, flags, max_active, args...) \
394 __alloc_workqueue_key((fmt), (flags), (max_active), \
b196be89 395 NULL, NULL, ##args)
4e6045f1
JB
396#endif
397
81dcaf65
TH
398/**
399 * alloc_ordered_workqueue - allocate an ordered workqueue
b196be89 400 * @fmt: printf format for the name of the workqueue
58a69cb4 401 * @flags: WQ_* flags (only WQ_FREEZABLE and WQ_MEM_RECLAIM are meaningful)
355c0663 402 * @args...: args for @fmt
81dcaf65
TH
403 *
404 * Allocate an ordered workqueue. An ordered workqueue executes at
405 * most one work item at any given time in the queued order. They are
406 * implemented as unbound workqueues with @max_active of one.
407 *
408 * RETURNS:
409 * Pointer to the allocated workqueue on success, %NULL on failure.
410 */
ee64e7f6 411#define alloc_ordered_workqueue(fmt, flags, args...) \
8719dcea 412 alloc_workqueue(fmt, WQ_UNBOUND | __WQ_ORDERED | (flags), 1, ##args)
81dcaf65 413
ee64e7f6 414#define create_workqueue(name) \
23d11a58 415 alloc_workqueue("%s", __WQ_LEGACY | WQ_MEM_RECLAIM, 1, (name))
ee64e7f6 416#define create_freezable_workqueue(name) \
23d11a58
TH
417 alloc_workqueue("%s", __WQ_LEGACY | WQ_FREEZABLE | WQ_UNBOUND | \
418 WQ_MEM_RECLAIM, 1, (name))
ee64e7f6 419#define create_singlethread_workqueue(name) \
23d11a58 420 alloc_ordered_workqueue("%s", __WQ_LEGACY | WQ_MEM_RECLAIM, name)
1da177e4
LT
421
422extern void destroy_workqueue(struct workqueue_struct *wq);
423
7a4e344c
TH
424struct workqueue_attrs *alloc_workqueue_attrs(gfp_t gfp_mask);
425void free_workqueue_attrs(struct workqueue_attrs *attrs);
9e8cd2f5
TH
426int apply_workqueue_attrs(struct workqueue_struct *wq,
427 const struct workqueue_attrs *attrs);
042f7df1 428int workqueue_set_unbound_cpumask(cpumask_var_t cpumask);
7a4e344c 429
d4283e93 430extern bool queue_work_on(int cpu, struct workqueue_struct *wq,
c1a220e7 431 struct work_struct *work);
d4283e93 432extern bool queue_delayed_work_on(int cpu, struct workqueue_struct *wq,
28e53bdd 433 struct delayed_work *work, unsigned long delay);
8376fe22
TH
434extern bool mod_delayed_work_on(int cpu, struct workqueue_struct *wq,
435 struct delayed_work *dwork, unsigned long delay);
28e53bdd 436
b3c97528 437extern void flush_workqueue(struct workqueue_struct *wq);
9c5a2ba7 438extern void drain_workqueue(struct workqueue_struct *wq);
1da177e4 439
65f27f38 440extern int schedule_on_each_cpu(work_func_t func);
1da177e4 441
65f27f38 442int execute_in_process_context(work_func_t fn, struct execute_work *);
1da177e4 443
401a8d04
TH
444extern bool flush_work(struct work_struct *work);
445extern bool cancel_work_sync(struct work_struct *work);
446
447extern bool flush_delayed_work(struct delayed_work *dwork);
57b30ae7 448extern bool cancel_delayed_work(struct delayed_work *dwork);
401a8d04 449extern bool cancel_delayed_work_sync(struct delayed_work *dwork);
28e53bdd 450
dcd989cb
TH
451extern void workqueue_set_max_active(struct workqueue_struct *wq,
452 int max_active);
e6267616 453extern bool current_is_workqueue_rescuer(void);
d84ff051 454extern bool workqueue_congested(int cpu, struct workqueue_struct *wq);
dcd989cb 455extern unsigned int work_busy(struct work_struct *work);
3d1cb205
TH
456extern __printf(1, 2) void set_worker_desc(const char *fmt, ...);
457extern void print_worker_info(const char *log_lvl, struct task_struct *task);
3494fc30 458extern void show_workqueue_state(void);
dcd989cb 459
8425e3d5
TH
460/**
461 * queue_work - queue work on a workqueue
462 * @wq: workqueue to use
463 * @work: work to queue
464 *
465 * Returns %false if @work was already on a queue, %true otherwise.
466 *
467 * We queue the work to the CPU on which it was submitted, but if the CPU dies
468 * it can be processed by another CPU.
469 */
470static inline bool queue_work(struct workqueue_struct *wq,
471 struct work_struct *work)
472{
473 return queue_work_on(WORK_CPU_UNBOUND, wq, work);
474}
475
476/**
477 * queue_delayed_work - queue work on a workqueue after delay
478 * @wq: workqueue to use
479 * @dwork: delayable work to queue
480 * @delay: number of jiffies to wait before queueing
481 *
482 * Equivalent to queue_delayed_work_on() but tries to use the local CPU.
483 */
484static inline bool queue_delayed_work(struct workqueue_struct *wq,
485 struct delayed_work *dwork,
486 unsigned long delay)
487{
488 return queue_delayed_work_on(WORK_CPU_UNBOUND, wq, dwork, delay);
489}
490
491/**
492 * mod_delayed_work - modify delay of or queue a delayed work
493 * @wq: workqueue to use
494 * @dwork: work to queue
495 * @delay: number of jiffies to wait before queueing
496 *
497 * mod_delayed_work_on() on local CPU.
498 */
499static inline bool mod_delayed_work(struct workqueue_struct *wq,
500 struct delayed_work *dwork,
501 unsigned long delay)
502{
503 return mod_delayed_work_on(WORK_CPU_UNBOUND, wq, dwork, delay);
504}
505
506/**
507 * schedule_work_on - put work task on a specific cpu
508 * @cpu: cpu to put the work task on
509 * @work: job to be done
510 *
511 * This puts a job on a specific cpu
512 */
513static inline bool schedule_work_on(int cpu, struct work_struct *work)
514{
515 return queue_work_on(cpu, system_wq, work);
516}
517
518/**
519 * schedule_work - put work task in global workqueue
520 * @work: job to be done
521 *
522 * Returns %false if @work was already on the kernel-global workqueue and
523 * %true otherwise.
524 *
525 * This puts a job in the kernel-global workqueue if it was not already
526 * queued and leaves it in the same position on the kernel-global
527 * workqueue otherwise.
528 */
529static inline bool schedule_work(struct work_struct *work)
530{
531 return queue_work(system_wq, work);
532}
533
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534/**
535 * flush_scheduled_work - ensure that any scheduled work has run to completion.
536 *
537 * Forces execution of the kernel-global workqueue and blocks until its
538 * completion.
539 *
540 * Think twice before calling this function! It's very easy to get into
541 * trouble if you don't take great care. Either of the following situations
542 * will lead to deadlock:
543 *
544 * One of the work items currently on the workqueue needs to acquire
545 * a lock held by your code or its caller.
546 *
547 * Your code is running in the context of a work routine.
548 *
549 * They will be detected by lockdep when they occur, but the first might not
550 * occur very often. It depends on what work items are on the workqueue and
551 * what locks they need, which you have no control over.
552 *
553 * In most situations flushing the entire workqueue is overkill; you merely
554 * need to know that a particular work item isn't queued and isn't running.
555 * In such cases you should use cancel_delayed_work_sync() or
556 * cancel_work_sync() instead.
557 */
558static inline void flush_scheduled_work(void)
559{
560 flush_workqueue(system_wq);
561}
562
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563/**
564 * schedule_delayed_work_on - queue work in global workqueue on CPU after delay
565 * @cpu: cpu to use
566 * @dwork: job to be done
567 * @delay: number of jiffies to wait
568 *
569 * After waiting for a given time this puts a job in the kernel-global
570 * workqueue on the specified CPU.
571 */
572static inline bool schedule_delayed_work_on(int cpu, struct delayed_work *dwork,
573 unsigned long delay)
574{
575 return queue_delayed_work_on(cpu, system_wq, dwork, delay);
576}
577
578/**
579 * schedule_delayed_work - put work task in global workqueue after delay
580 * @dwork: job to be done
581 * @delay: number of jiffies to wait or 0 for immediate execution
582 *
583 * After waiting for a given time this puts a job in the kernel-global
584 * workqueue.
585 */
586static inline bool schedule_delayed_work(struct delayed_work *dwork,
587 unsigned long delay)
588{
589 return queue_delayed_work(system_wq, dwork, delay);
590}
591
592/**
593 * keventd_up - is workqueue initialized yet?
594 */
595static inline bool keventd_up(void)
596{
597 return system_wq != NULL;
598}
599
2d3854a3 600#ifndef CONFIG_SMP
d84ff051 601static inline long work_on_cpu(int cpu, long (*fn)(void *), void *arg)
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602{
603 return fn(arg);
604}
605#else
d84ff051 606long work_on_cpu(int cpu, long (*fn)(void *), void *arg);
2d3854a3 607#endif /* CONFIG_SMP */
a25909a4 608
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609#ifdef CONFIG_FREEZER
610extern void freeze_workqueues_begin(void);
611extern bool freeze_workqueues_busy(void);
612extern void thaw_workqueues(void);
613#endif /* CONFIG_FREEZER */
614
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615#ifdef CONFIG_SYSFS
616int workqueue_sysfs_register(struct workqueue_struct *wq);
617#else /* CONFIG_SYSFS */
618static inline int workqueue_sysfs_register(struct workqueue_struct *wq)
619{ return 0; }
620#endif /* CONFIG_SYSFS */
621
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622#ifdef CONFIG_WQ_WATCHDOG
623void wq_watchdog_touch(int cpu);
624#else /* CONFIG_WQ_WATCHDOG */
625static inline void wq_watchdog_touch(int cpu) { }
626#endif /* CONFIG_WQ_WATCHDOG */
627
1da177e4 628#endif